A. Buel Trowbridge, 82, a professor-emeritus at American University, where he taught Russian history at the School of International Service, died Tuesday at Georgetown University Hospital following a stroke.

Mr. Trowbridge, who was born at Ithaca, N.Y., graduated from Cornell University in 1920 and then went to Oxford University on a Rhodes Scholarship. From 1927 to 1933, he taught at the Hill School in Pottstown, Pa., and then at Phillips Academy in Andover, Mass. From 1933 to 1943, he taught religious philosphy at Rollins College in Winter Park, Fla. He earned a master's degree at Union Theological Seminary at Columbia University in New York in 1936.

During World War II, Mr. Trowbridge served with the Red Cross in North Africa and Italy. After the war, he directed the Carnegie Endowment Office in Paris and then became a State Department officer in charge of civilian affairs in Heidenheim, Germany, during the occupation.

From 1952 to 1955, he was head of the UNESCO Fundamental Education Mission in Iraq. He then returned to the United States and joined the faculty of American University in 1956. He retired in 1972 and was named professor-emeritus at that time.

Mr. Trowbridge, who lived in McLean, was a former chairman of the Washington area chapter of the United Nations Association and a member of the board of the Hattie M. Strong Foundation, which is engaged in educational and cultural activities. He was the author of two books, "Religion for Our Times," which was published in 1963, and "An Auld Acquaintance Who'll Ne'er Be Forgot," which appeared in 1976.

Survivors include his wife, Louise Thorne Trowbridge of McLean; one son, Alexander B. Trowbridge III of Washington; two daughters, Judy T. Cullen of Lopez, Wash., and Joya Bovingdon Cox of Washington; a twin sister, Alice T. Strong of Washington and Annapolis; 11 grandchildren, and four great-grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to The International Student House, 1825 R St. NW, Washington, D.C.